In a liquid crystal display, both surfaces of a liquid crystal cell in which a liquid crystal is retained are generally provided with a polarizing plate. In order to visually compensate for retardation caused by birefringence of the liquid crystal cell in a front direction and an oblique direction, a birefringent layer as an optical compensation layer is disposed between the liquid crystal cell and each of the polarizing plates. In practice, the optical compensation layer and the polarizing plate usually are formed as one piece serving as a polarizing plate with an optical compensation layer (see JP 5(1993)-27118 A and JP 5(1993)-27119 A, for example).
Such a polarizing plate with an optical compensation layer generally has a configuration in which a first pressure-sensitive adhesive layer is formed on one surface of the optical compensation layer and the polarizing plate is made to adhere thereto via this pressure-sensitive adhesive layer. In the polarizing plate with the optical compensation layer, a second pressure-sensitive adhesive layer usually is formed on the other surface of the optical compensation layer. Via this second pressure-sensitive adhesive layer, the polarizing plate with the optical compensation layer is made to adhere to a glass substrate of a liquid crystal cell or the like, so that the polarizing plate with the optical compensation layer is disposed in the liquid crystal display.
For a practical use, the pressure-sensitive adhesive layers have to have some performances, for example, adhesion durability, which prevents partial peeling caused by heat or moisture. On the other hand, if the polarizing plate with the optical compensation layer as described above and the glass substrate are displaced from each other or they inadvertently sandwich foreign matters between them at the time of mounting the polarizing plate on the glass substrate, for example, the polarizing plate has to be peeled off and attached again to the glass substrate. Accordingly, the above-noted pressure-sensitive adhesive layers also need to have reworkability, which allows repeated peeling and attaching. Especially at the time of peeling, there are some cases where the pressure-sensitive adhesive layer is not completely removed and remains on the glass substrate, which is called adhesive residue. In such cases, it takes great effort to reattach the polarizing plate with the optical compensation layer. Moreover, in the case where the pressure-sensitive adhesive and the surface of the glass substrate adhere to each other firmly, the power of peeling the polarizing plate with the optical compensation layer may break the optical compensation layer and a liquid crystal display panel, etc., for example.